To disable a SIGCHLD signal handler use SIG_DFL, *not* SIG_IGN

which now has a different meaning.

1 files changed, 123 insertions, 60 deletions

diff --git a/usr.sbin/lpr/lpd/lpd.c b/usr.sbin/lpr/lpd/lpd.c
index 6d38a974c54..fe1824eb3fe 100644
--- a/usr.sbin/lpr/lpd/lpd.c
+++ b/usr.sbin/lpr/lpd/lpd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: lpd.c,v 1.24 2001/12/06 03:12:30 ericj Exp $ */
+/*	$OpenBSD: lpd.c,v 1.25 2002/01/07 03:44:30 millert Exp $ */
 /*	$NetBSD: lpd.c,v 1.7 1996/04/24 14:54:06 mrg Exp $	*/
 
 /*
@@ -45,7 +45,7 @@ static const char copyright[] =
 #if 0
 static const char sccsid[] = "@(#)lpd.c	8.7 (Berkeley) 5/10/95";
 #else
-static const char rcsid[] = "$OpenBSD: lpd.c,v 1.24 2001/12/06 03:12:30 ericj Exp $";
+static const char rcsid[] = "$OpenBSD: lpd.c,v 1.25 2002/01/07 03:44:30 millert Exp $";
 #endif
 #endif /* not lint */
 
@@ -92,6 +92,7 @@ static const char rcsid[] = "$OpenBSD: lpd.c,v 1.24 2001/12/06 03:12:30 ericj Ex
 #include <unistd.h>
 #include <syslog.h>
 #include <signal.h>
+#include <err.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <dirent.h>
@@ -99,22 +100,31 @@ static const char rcsid[] = "$OpenBSD: lpd.c,v 1.24 2001/12/06 03:12:30 ericj Ex
 #include <stdlib.h>
 #include <string.h>
 #include <ctype.h>
+
 #include "lp.h"
 #include "lp.local.h"
 #include "pathnames.h"
 #include "extern.h"
 
-extern int __ivaliduser __P((FILE *, in_addr_t, const char *, const char *));
+#define	LPD_NOPORTCHK	0001		/* skip reserved-port check */
 
 int	lflag;				/* log requests flag */
+int	rflag;				/* allow 'of' for remote printers */
+int	sflag;				/* secure (no inet) flag */
 int	from_remote;			/* from remote socket */
+uid_t	uid;				/* real uid */
+uid_t	euid;				/* effective uid */
+volatile sig_atomic_t child_count;	/* number of kids forked */
+
+static void        reapchild __P((int));
+static void        mcleanup __P((int));
+static void        doit __P((void));
+static void        startup __P((void));
+static void        chkhost __P((struct sockaddr_in *));
+static int	   ckqueue __P((char *));
+static __dead void usage __P((void));
 
-static void       reapchild __P((int));
-static void       mcleanup __P((int));
-static void       doit __P((void));
-static void       startup __P((void));
-static void       chkhost __P((struct sockaddr_in *));
-static int	  ckqueue __P((char *));
+extern int __ivaliduser __P((FILE *, in_addr_t, const char *, const char *));
 
 /* unused, needed for lpc */
 volatile sig_atomic_t gotintr;
@@ -122,39 +132,66 @@ volatile sig_atomic_t gotintr;
 uid_t	uid, euid;
 
 int
-main(argc, argv)
-	int argc;
-	char **argv;
+main(int argc, char **argv)
 {
-	int f, lfd, funix, finet, options, fromlen;
+	int f, funix, finet, options, check_options, fromlen, ch, lfd;
 	fd_set defreadfds;
+	long child_max = 32;	/* more then enough to hose the system */
 	int maxfd = 0;
+	char *cp;
 	struct sockaddr_un un, fromunix;
 	struct sockaddr_in sin, frominet;
 	sigset_t mask, omask;
 
 	euid = geteuid();	/* these shouldn't be different */
 	uid = getuid();
-	options = 0;
+	options = check_options = 0;
 	gethostname(host, sizeof(host));
 
-	if (euid != 0) {
-		fprintf(stderr,"lpd: must run as root\n");
-		exit(1);
-	}
+	if (euid != 0)
+		err(1, "must run as root");
 
-	while (--argc > 0) {
-		argv++;
-		if (argv[0][0] == '-')
-			switch (argv[0][1]) {
-			case 'd':
-				options |= SO_DEBUG;
-				break;
-			case 'l':
-				lflag++;
-				break;
-			}
+	while ((ch = getopt(argc, argv, "dln:rsw:W")) != -1) {
+		switch (ch) {
+		case 'd':
+			options |= SO_DEBUG;
+			break;
+		case 'l':
+			lflag++;
+			break;
+		case 'n':
+			child_max = strtol(optarg, &cp, 10);
+			if (*cp != '\0' || child_max < 0 || child_max > 1024)
+				errx(1, "invalid number of children: %s",
+				    optarg);
+		case 'r':
+			rflag++;
+			break;
+		case 's':
+			sflag++;
+			break;
+		case 'w':
+			wait_time = strtol(optarg, &cp, 10);
+			if (*cp != '\0' || wait_time < 0)
+				errx(1, "wait time must be postive integer: %s",
+				    optarg);
+			if (wait_time < 30)
+				warnx("warning: wait time less than 30 seconds");
+			break;
+		case 'W':
+			/*
+			 * Allow connections coming from a non-reserved port.
+			 * (done by some lpr-implementations for MS-Windows)
+			 */
+			check_options |= LPD_NOPORTCHK;
+			break;
+		default:
+			usage();
+			break;
+		}
 	}
+	argc -= optind;
+	argv += optind;
 
 #ifndef DEBUG
 	/*
@@ -165,7 +202,7 @@ main(argc, argv)
 
 	openlog("lpd", LOG_PID, LOG_LPR);
 	syslog(LOG_INFO, "restarted");
-	(void) umask(0);
+	(void)umask(0);
 	lfd = open(_PATH_MASTERLOCK, O_WRONLY|O_CREAT, 0644);
 	if (lfd < 0) {
 		syslog(LOG_ERR, "%s: %m", _PATH_MASTERLOCK);
@@ -181,7 +218,7 @@ main(argc, argv)
 	/*
 	 * write process id for others to know
 	 */
-	sprintf(line, "%u\n", getpid());
+	(void)snprintf(line, sizeof(line), "%u\n", getpid());
 	f = strlen(line);
 	if (write(lfd, line, f) != f) {
 		syslog(LOG_ERR, "%s: %m", _PATH_MASTERLOCK);
@@ -192,8 +229,8 @@ main(argc, argv)
 	 * Restart all the printers.
 	 */
 	startup();
-	(void) unlink(_PATH_SOCKETNAME);
-	funix = socket(AF_UNIX, SOCK_STREAM, 0);
+	(void)unlink(_PATH_SOCKETNAME);
+	funix = socket(AF_LOCAL, SOCK_STREAM, 0);
 	if (funix < 0) {
 		syslog(LOG_ERR, "socket: %m");
 		exit(1);
@@ -204,14 +241,14 @@ main(argc, argv)
 	sigaddset(&mask, SIGQUIT);
 	sigaddset(&mask, SIGTERM);
 	sigprocmask(SIG_BLOCK, &mask, &omask);
-	(void) umask(07);
+	(void)umask(07);
 	signal(SIGHUP, mcleanup);
 	signal(SIGINT, mcleanup);
 	signal(SIGQUIT, mcleanup);
 	signal(SIGTERM, mcleanup);
 	memset(&un, 0, sizeof(un));
-	un.sun_family = AF_UNIX;
-	strcpy(un.sun_path, _PATH_SOCKETNAME);
+	un.sun_family = AF_LOCAL;
+	strlcpy(un.sun_path, _PATH_SOCKETNAME, sizeof(un.sun_path));
 #ifndef SUN_LEN
 #define SUN_LEN(unp) (strlen((unp)->sun_path) + 2)
 #endif
@@ -219,14 +256,14 @@ main(argc, argv)
 		syslog(LOG_ERR, "ubind: %m");
 		exit(1);
 	}
-	(void) umask(0);
+	(void)umask(0);
 	sigprocmask(SIG_SETMASK, &omask, NULL);
 	FD_ZERO(&defreadfds);
 	FD_SET(funix, &defreadfds);
 	if (funix > maxfd)
 		maxfd = funix;
 	listen(funix, 5);
-	finet = socket(AF_INET, SOCK_STREAM, 0);
+	finet = sflag ? -1 : socket(AF_INET, SOCK_STREAM, 0);
 	if (finet >= 0) {
 		struct servent *sp;
 
@@ -237,7 +274,7 @@ main(argc, argv)
 			}
 		}
 		f = 1;
-		(void) setsockopt(finet, SOL_SOCKET, SO_REUSEADDR, &f,
+		(void)setsockopt(finet, SOL_SOCKET, SO_REUSEADDR, &f,
 		    sizeof(f));
 		sp = getservbyname("printer", "tcp");
 		if (sp == NULL) {
@@ -264,6 +301,19 @@ main(argc, argv)
 	for (;;) {
 		int domain, nfds, s;
 		fd_set readfds;
+		short sleeptime = 10;	/* overflows in about 2 hours */
+
+		while (child_max < child_count) {
+			syslog(LOG_WARNING,
+			    "too many children, sleeping for %d seconds",
+			    sleeptime);
+			sleep(sleeptime);
+			sleeptime <<= 1;
+			if (sleeptime < 0) {
+				syslog(LOG_CRIT, "sleeptime overflowed! help!");
+				sleeptime = 10;
+			}
+		}
 
 		FD_COPY(&defreadfds, &readfds);
 		nfds = select(maxfd + 1, &readfds, 0, 0, 0);
@@ -273,7 +323,7 @@ main(argc, argv)
 			continue;
 		}
 		if (FD_ISSET(funix, &readfds)) {
-			domain = AF_UNIX, fromlen = sizeof(fromunix);
+			domain = AF_LOCAL, fromlen = sizeof(fromunix);
 			s = accept(funix,
 			    (struct sockaddr *)&fromunix, &fromlen);
 		} else /* if (FD_ISSET(finet, &readfds)) */  {
@@ -290,17 +340,19 @@ main(argc, argv)
 				syslog(LOG_WARNING, "accept: %m");
 			continue;
 		}
-		if (fork() == 0) {
-			signal(SIGCHLD, SIG_IGN);
+		switch (fork()) {
+		case 0:
+			signal(SIGCHLD, SIG_DFL);
 			signal(SIGHUP, SIG_IGN);
 			signal(SIGINT, SIG_IGN);
 			signal(SIGQUIT, SIG_IGN);
 			signal(SIGTERM, SIG_IGN);
-			(void) close(funix);
-			(void) close(finet);
+			(void)close(funix);
+			if (finet != -1)
+				(void)close(finet);
 			if (s != STDOUT_FILENO) {
 				dup2(s, STDOUT_FILENO);
-				(void) close(s);
+				(void)close(s);
 			}
 			if (domain == AF_INET) {
 				from_remote = 1;
@@ -309,26 +361,30 @@ main(argc, argv)
 				from_remote = 0;
 			doit();
 			exit(0);
+		case -1:
+			syslog(LOG_WARNING, "fork: %m, sleeping for 10 seconds...");
+			sleep(10);
+			continue;
+		default:
+			child_count++;
 		}
-		(void) close(s);
+		(void)close(s);
 	}
 }
 
 static void
-reapchild(signo)
-	int signo;
+reapchild(int signo)
 {
 	int save_errno = errno;
 	int status;
 
 	while (waitpid((pid_t)-1, &status, WNOHANG) > 0)
-		;
+		child_count--;
 	errno = save_errno;
 }
 
 static void
-mcleanup(signo)
-	int signo;
+mcleanup(int signo)
 {
 	struct syslog_data sdata = SYSLOG_DATA_INIT;
 
@@ -359,7 +415,7 @@ char	*cmdnames[] = {
 };
 
 static void
-doit()
+doit(void)
 {
 	char *cp;
 	int n;
@@ -467,7 +523,7 @@ doit()
  * files left from the last time the machine went down.
  */
 static void
-startup()
+startup(void)
 {
 	char *buf;
 	char *cp;
@@ -506,8 +562,7 @@ startup()
  * Make sure there's some work to do before forking off a child
  */
 static int
-ckqueue(cap)
-	char *cap;
+ckqueue(char *cap)
 {
 	struct dirent *d;
 	DIR *dirp;
@@ -533,8 +588,7 @@ ckqueue(cap)
  * Check to see if the from host has access to the line printer.
  */
 static void
-chkhost(f)
-	struct sockaddr_in *f;
+chkhost(struct sockaddr_in *f)
 {
 	struct hostent *hp;
 	FILE *hostf;
@@ -548,7 +602,7 @@ chkhost(f)
 		fatal("Host name for your address (%s) unknown",
 			inet_ntoa(f->sin_addr));
 
-	(void) strlcpy(fromb, hp->h_name, sizeof(fromb));
+	(void)strlcpy(fromb, hp->h_name, sizeof(fromb));
 	from = fromb;
 
 	/* Check for spoof, ala rlogind */
@@ -570,10 +624,10 @@ again:
 	if (hostf) {
 		if (__ivaliduser(hostf, f->sin_addr.s_addr,
 		    DUMMY, DUMMY) == 0) {
-			(void) fclose(hostf);
+			(void)fclose(hostf);
 			return;
 		}
-		(void) fclose(hostf);
+		(void)fclose(hostf);
 	}
 	if (first == 1) {
 		first = 0;
@@ -583,3 +637,12 @@ again:
 	fatal("Your host does not have line printer access");
 	/*NOTREACHED*/
 }
+
+static void
+usage(void)
+{
+	extern char *__progname;
+
+	fprintf(stderr, "usage: %s [-dls]\n", __progname);
+	exit(1);
+}